Module 16: The Respiratory System

Question 1

functions of respiratory system

Answer 1

continuous supply of oxygen for metabolic activities
Removal of CO2
Regulation of pH of blood

Question 2

Processes of respiratory system

Answer 2

pulmonary ventilation
external respiration
transport of respiratory gases
internal respiration

Question 3

Pulmonary ventilation

Answer 3

aka breathing in and out

Question 4

External respiration

Answer 4

exchange of gases between blood and lungs

Question 5

Transport of respiratory gases

Answer 5

gases are transported in RBC and blood plasma

Question 6

Internal respiration

Answer 6

exchange of gases between blood and tissue cells

Question 7

Structures of respiratory system (2 zones)

Answer 7

conducting zone (macroscopic)
respiratory zone (microscopic)

Question 8

Conducting zone consists of

Answer 8

passageways for the conduction of air
nose
pharynx (throat)
Larynx (voice box)
Trachea (windpipe)
Bronchi
Terminal bronchioles

Question 9

Functions of conducting zone - nose

Answer 9

Provides airway for respiration
moistens and warms air
cleans and filters unwanted particles
aids in speech
provides a sight for the olfactory receptors

Question 10

Parts of the nose:

Answer 10

External nares: Nostrils, anterior portion is vestibule
Nasal cavities: separated by nasal septum; 3 bony projections called conchae; sticky mucus traps foreign particles
Internal nares: opening between nose and throat
Paranasal sinuses: maxillary, frontal, ethmoidal and sphenoidal sinuses

Question 11

Pharynx

Answer 11

aka throat

consists of nasopharynx (air), oropharynx and laryngopharynx(food and air)

Question 12

Larynx

Answer 12

aka voice box
contains vocal cords
connects pharynx to trachea
epiglottis covers opening of larynx

Question 13

Trachea

Answer 13

aka windpipe
provides passageway for air to move in and out of lungs
Cleans warms and moistens incoming air

Question 14

Bronchi

Answer 14

Trachea branches into left bronchus and right bronchus which lead to each lung

Question 15

Terminal bronchioles

Answer 15

provide the passageway into the respiratory zone

Question 16

Respiratory zone (microscopic)

Answer 16

respiratory bronchioles and alveolar ducts

Question 17

Respiratory bronchioles

Answer 17

formed from branchings of the terminal bronchioles

Question 18

Alveolar ducts

Answer 18

respiratory bronchioles lead into ducts

Ducts lead into clusters of alveoli

Question 19

Alveoli (air sacs)

Answer 19

provide surface area for exchange of gases

found in clusters called alveolar sacs

Question 20

3 types of cells in alveoli

Answer 20

Type I alveolar (simple squamous epithelium) provide site for gas exchange
Type II alveolar (septal cells) produce surfactant (compound that prevents alveoli from collapsing)
Macrophages (dust cells) clean up foreign material

Question 21

Structure of the lungs

Answer 21

weigh 1kg
soft spongy and elastic
Take up all of thoracic cavity
Cone shaped
Each lung encased in pleura sac
base sits on diaphragm

Question 22

Hilus

Answer 22

area in each lung where blood vessels, lymphatic vessels, nerves and the bronchus enter and leave the lung

Question 23

lobes in lungs

Answer 23

right lung has 3 lobes (55% of gas exchange)

left lung has 2 lobes (45% of gas exchange)

Question 24

Lobes of lungs are divided into

Answer 24

bronchopulmonary segments

Question 25

Lobules

Answer 25

small macroscopic subdivisions of bronchopulmonary segments

Question 26

2 layers of pleura

Answer 26

visceral layer hugs lung surface | Parietal layer lines thoracic wall and upper surface of diaphragm

Question 27

During normal inhalation (inspiration)

Answer 27

thoracic volume increases | pressure in lungs decreases

Question 28

During normal exhalation (expiration)

Answer 28

pressure in lungs increases and forces air out of the lungs | Thoracic volume decreases

Question 29

Gas exchange in lungs

Answer 29

air inhaled o2 from air diffuses from alveoli into capillaries CO2 diffuses from capillaries into the alveoli CO2 is exhaled

Question 30

Gas exchange in body cells

Answer 30

oxygen leaves capillary blood and diffuses into the cells where it can be used during cellular metabolism Co2 diffuses into the capillary blood as metabolism occurs in the cell

Question 31

Transportation of oxygen

Answer 31

diffuses across alveoli into capillaries O2 then dissolves in plasma 3% of O2 is transported as dissolved gas 97% of O2 is carried by Hb molecules

Question 32

Transport of CO2

Answer 32

diffuses from tissue cells into capillaries 7% dissolved in plasma 23% with Hb in RBC 70% as bicarbonate ions in plasma

Question 33

Medullary rhythmicity center

Answer 33

``` sets basic pattern of respiration inspiration lasts 2 seconds expiration lasts 3 seconds normally 12-20 breaths per min in adult 20-40 in children ```

Question 34

Chemical control of respiration

Answer 34

chemoreceptors are stimulated and relay messages to the brain Central and peripheral

Question 35

Central chemoreceptors

Answer 35

found in CNS (in medulla) | sensitive to increases in CO2 and H+ levels

Question 36

Peripheral chemoreceptors

Answer 36

found in PNS (walls of carotid arteries and in aorta) | Detect decreases in oxygen levels

Question 37

Factors that influence breathing

Answer 37

``` yawning sneezing coughing hiccupping crying laughing ```

Question 38

Bronchitis

Answer 38

inflammation of bronchial tubes | coughing up sputum

Question 39

Laryngitis

Answer 39

inflammation of larynx | dry, sore throat with hoarse or no voice

Question 40

Pneumonia

Answer 40

inflammation of lungs | inflamed lungs, high fever, cough, sputum with pus and blood

Question 41

sinusitis

Answer 41

inflammation of sinuses | inflammation of paranasal cavities, headaches, pain, pressure in the bones of the face

Question 42

Pharyngitis

Answer 42

Inflammation of the pharynx | sore throat and fever

Question 43

Bacterial diseases

Answer 43

``` bronchitis laryngitis pneumonia sinusitis pharyngitis ```

Question 44

Viral diseases

Answer 44

influenza | common cold

Question 45

Respiratory distress syndrome (RDS)

Answer 45

aka Hyaline membrane disease (HMD) most common cause of death in newborn caused by deficient amount of surfactant Difficulty breathing (exhausts the infant)

Question 46

Lung cancer

Answer 46

accounts for 30% of all cancer deaths most patients die within one year of diagnosis 85-90% of lung cancers are due to cigarette smoke

Question 47

asthma

Answer 47

inflammatory disorder narrowing of airways coughing, difficulty breathing, wheezing

Question 48

Aging and the respiratory system

Answer 48

lung capacity decreases lungs becomes less elastic (oxygen delivery to tissue cells is impaired) Elderly more susceptible to diseases due to decreases activity of macrophages